Issues and resolution

A named reference was invoked but never defined. The reference may be defined inline or in the reference list. You may have misspelled the reference name, or used special characters that look the same but are actually different.

For instance,

<ref name="foo-bar">content</ref>

and

<ref name="foo–bar">content</ref>

are not the same: one contains a hyphen while the other uses an ndash. To avoid this sort of error, try to use only the characters available on the standard keyboard.

You may have also invoked a reference but never defined it, for example: <ref name="foo–bar">...</ref> or <ref name="foo–bar" />.

You may have tried to include the reference inside the ref tag, for example: <ref foo–bar />.

The full reference may have been removed from the article with other content, such as when removing information under BLP concerns. In this case the text of the reference will be available in the page history, and you can convert the single <ref /> tag into a full reference.

The closing </ref> tag is missing or malformed. This would normally result in a A <ref> tag is missing the closing </ref> (see the help page).

message, but the missing tag causes the reference to "eat" the reference following in the list. Since that reference is undefined, the The named reference $1 was invoked but never defined (see the help page).
for both references. This can be very confusing, as the order of references in the list may not match the order used in the content.

If {{reflist}} is used and the |refs= parameter is missing or malformed.

If a named reference is invoked within the reference list markup:

{{reflist|refs=
<ref name=refname1 />
}}

Display

If the reference name includes characters other than standard English alphabet and numerals, then those characters will be dot encoded. That is, the characters will be converted to ASCII hexadecimal and shown with a period before them. For example, a name such as $$abcd would show as .24.24abcd. As noted at WP:NAMEDREFS: "Please consider keeping names simple and restricted to the standard English alphabet and numerals."

Examples

The content of this message is dependent on the language setting in Special:Preferences. You can test how the error messages look in the most popular languages with these links: